Hi Micky, Welcome to the forum. I'm not quite sure about the Pro 575, but on my Ironwood 650 it's really quick. I fired it up last night with the temperature around 60 degrees F outside. I started the clock once it finished with the ignite process. It took 13 1/2 minutes to reach operating temps (400 degrees). I noticed the grill says preheating is finished about 10 degrees before the set temperature.